<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="root"></div>
</body>

</html>
<script src="https://unpkg.com/vue@next"></script>
<script>
    // toRef
    const app = Vue.createApp({
        template: `
        <div>{{age}}</div>
        `,
        setup(props, context) {
            const {reactive,toRef} =Vue;
            const data=reactive({name:'dell'});
            const age=toRef(data,'age')
            setTimeout(() => {
                age.value='lee'
            }, 2000);
            return {age}
        }
    })
    const vm = app.mount('#root')
</script>